Just In Time(23.02.2009)

Spot-light

By P.Chandra Bose Sengu

Innovations

“ Plug & Work “

1

CONTENT 1. Introduction 2. History of JIT 3. Philosophy of JIT 4. Aspects to JIT 5. Benefits of JIT 6. Key Elements of JIT 7. Drawbacks 8. System 9. Conclusion 10. References

INTRODUCTION Just-In-Time(JIT) is defined in “ a philosophy of manufacturing based on planned elimination of all waste and on continuous improvement of productivity”.

It also has been described as an approach with the objective of producing the right part in the right place at the right time (in other words, “Just In Time”)

Waste results from any activity that adds cost without adding value,

such as The unnecessary moving of materials, The accumulation of excess inventory, The use of faulty production method that create products requiring subsequent rework.

HISTORY OF JIT The technique was first used by the Ford Motor company during 1920s. But the technique was subsequently adopted and publicised by Toyota Motor Corporation of Japan as part of its Toyota production System(TPS). In 1954 Japanese giant Toyota implemented this concept in order to reduce wasteful overstocking in car production.

PHILOSOPHY OF JIT Just In Time(JIT) inventory systems are not just a simple method that a company has buy in to: it has a whole philosophy that the company must follow. The ideas in this philosophy come from many different disciplines including; Statistics, Industrial engineering, Production management and Behavioral science.

The Toyota Production System is built on two main principles:

1. Just-In-Time 2. Jidoka

There are two aspects to JIT Just in time production Just in Purchasing.

JIT production is defined as “A system which is driven by demand for finished products, whereby each component on production line is produced only when needed for the next stage.”

JIT seeks to achieve the following goals.

1.

Estimation of non-value added activities

2.

Zero inventory

3.

Batch size of one

4.

A 100% on time delivery service.

The following are the key features of JIT production. •

The production line is run on a demand pull basis, so that activity of each work station is authorised by the demand of downstream work stations.

•

Set-up time and manufacturing lead time are minimised.

BENEFITS OF JIT •

Reduced set up times

•

Improved flows of goods

•

Employees who possess multi-skills are utilized more efficiently.

•

Better consistency of scheduling and consistency of employee work hours.

•

Increased emphasis on supplier relationships.

•

Supplies continue around the clock keeping workers productive and businesses focused on turnover.

The main benefit of JIT is that it can improve production efficiency and therefore competitiveness. •

Preventing over-production

•

Minimising waiting times and transport costs

•

Saving resources by streamlining your production systems

•

Reducing the capital you have tied up in stock

•

Dispensing with the need for inventory operations

•

Decreasing product defects

Key Elements of JIT •

Uniform Plant loading

•

Reduce or eliminate setup times

•

Reduce lot sizes (manufacturing and purchase)

•

Reduce lead time (production and delivery)

•

Preventive maintenance

•

Flexible work force

•

Require supplier quality assurance implement a zero defects quality program

•

Small-lot (single unit)

and

JIT has the following major drawbacks:

· Culture Differences The cultures vary from firm to firm.

· Traditional Approach The traditional approach in manufacturing is to store up a large amount of inventory in the means of backing up during bad time.

· Difference in implementation of JIT Because JIT was originally established in Japanese, it is somehow different for implementing in western countries. The benefits may vary.

· Loss of individual autonomy This is mainly due to the shorter cycle times which adds pressures and stress on the workers.

· Loss of team autonomy This is the result of decreasing buffer inventories which lead to a lower flexibility of the workers to solve problem individually.

· Loss of method autonomy It means the workers must act some way when problems occur, this does not allow them to have their own method to solve a problem.

· JIT success is varied from industry to industry Some industries are benefit more from JIT while others do not.

· Relationship between management and employees is important · Employee commitment Employees must commit to JIT, to enhance the quality as their ultimate goal.

· Production level JIT works best for medium to high range of production volume.

· Employee skill JIT requires workers to be multi-skilled and flexible to change.

· Compensation should be set on time based wages. This allow the workers to concentrate on building what the customers wants.

The three major control phases of the productive system Information requirements for each end item over the planning horizon

Phase 1

Master production schedule

Lot sizing rules and capacity planning

Requirements for raw materials

Phase 2

Materials requirements planning system

Detailed shop floor schedule

Phase 3

Companies Currently using JIT •

Harley Davidson

•

Toyota Motor Company

•

General Motors

•

Ford Motor Company

•

Manufacturing Magic

•

Hawthorne Management Consulting

•

Strategy Manufacturing Inc.

CONCLUSION The implemented successfully it would eliminate waste, make the company more productive and more efficient. It does this through shorter transportation and increased communication. Although there are many companies that are successful, many companies are not. Even though there are enormous risks many still consider implementing JIT for it many advantages.

References………. Modern Machine Tools – April 2008 Production and Operations Management, - Himalaya publishing Internet http://www.wikipedia.org http://www.maaw.com/jitques.htm http://www.justintime.com/home.html